Lead bar for a retractable awning

ABSTRACT

A lead bar for a retractable awning is provided. The lead bar comprises an extruded hollow profile having longitudinal grooves for securing canvas and arms, respectively. The cross-section of the profile has a surrounding wall defining a wide region with portions placed away from a central axis, and an elongated region with elongated front and rear sections close to a mid-plane located between them. The elongated region projects in a downward direction from the lower portion of said wide region next to a front edge thereof. The securing grooves for canvas and arms are arranged on the upper portion and the lower portion of wide region respectively, substantially in directly opposite positions in relation to said central axis A partition wall separates the wide region from the elongated region.

TECHNICAL FIELD

The present invention concerns a lead bar for a retractable awning, of the type comprising a hollow profile produced by extrusion of a light metal alloy, such as aluminium.

STATE OF THE PREVIOUS ART

Retractable awnings comprising a canvas with a rear edge attached to a rolling-up tube rotatably mounted at its ends to rotate on brackets fixed to a wall or other structure, and a front edge attached to a rigid bar so called “lead bar” are well-known in the art. Connected to the roll-up tube there is a mechanism that can be operated either manually or by motor in order to rotate the tube in one or the other directions so that the awning canvas is opened or closed. A pair of spring-loaded retractable arms are connected at one end to said wall or other structure and at the other end to the lead bar so that they support the lead bar and apply a tension to the awning canvas. There are two main variants of this type of awning: those with rigid arms that are articulated at one end to the wall and attached at the other end to the lead bar, and that are foldable by oscillation in respective vertical planes, and those having arms each formed by two sections hinged together and articulated to the wall at one of their ends and to the lead bar at the other end, and that are elbow-like foldable in a common plane that is substantially parallel to the plane in which the awning canvas extends.

Throughout this document, the term “rear” is used to designate those parts that are closest to the wall or other structure on which the awning roll-up tube is mounted, and the term “front” is used to designate those parts that are furthest away from the wall or the roll-up tube. The terms “upper” and “lower” are used in its conventional sense referred to the lead bar when it is in a position corresponding to a substantially horizontal position of the arms. The terms “vertical” and “horizontal” in reference to the lead bar are also based on its position when the arms are in a substantially horizontal position.

The lead bar, especially when it has significant length, for example, four metres or more, is subjected to significant combined flexion and torsion forces. The directions in which the forces are produced depends on several factors, some variable, such as the arm and awning inclinations, the amount the awning canvas is extended, wind force and direction etc, together with others that are constant, such as arm type and arrangement, arm spring-load factor, the weight of the lead bar itself and that of the canvas, among others. There is a main flexion effort in a vertical plane due to the weight of the lead bar itself and to the arm supporting force. Also, there is a main flexion and torsion combined effort, being a flexion effort in the plane in which the canvas extends, and a torsion effort along the bar's longitudinal axis due to the tension in the canvas and to the thrust of arms. The tensions due to the variable factors are produced in variable planes or axes and are added to the previously mentioned main tensions. Consequently, there is a need for a lead bar adapted to adequately withstand the tensions produced by the combined main and variable efforts.

Document ES-A-1031627, to the present applicant, describes a lead bar constituted from a hollow profile made by aluminium extrusion, and which comprises longitudinal grooves designed for securing a front edge of the awning canvas and a front skirt, as well as other longitudinal grooves for securing the front ends of the arms. The mentioned profile presents an angular configuration formed by an elongated horizontal region and an elongated vertical region. A multiplicity of said longitudinal grooves enable the profile to be installed with the horizontal region in either the upper or lower positions, maintaining the vertical region in a front position. This profile also allows different options for securing the arms, whether these are rigid oscillating or elbow-like articulated. The mentioned elongated horizontal and vertical regions provide a good level of resistance against the flexion efforts in the vertical and horizontal planes, but are not so efficient against torsion efforts along the longitudinal axis of the bar and against combined flexion and torsion efforts in other variable and unpredictable planes.

Patent FR-A-2335686 relates to an awning leading bar made up of two or more extruded hollow profiles joined together by means of sections of cylindrical pipes that are plugged into the respective adjacent ends. To this end, the profile has a surrounding wall that defines three coaxial cylindrical portions, at least one of which links up along two corresponding generatrices with a pair of substantially straight sections that form a very open “V” cross-section that provides a certain amount of elasticity that is necessary to permit said piece of cylindrical connection piping to be plugged in. However, this same elasticity is an inconvenience with respect to withstanding the torsion efforts in the longitudinal axis of the bar, as well as the combined flexion and torsion efforts, since it facilitates the elastic deformation of the profile.

Patent ES-A-2029203 describes an awning comprising a lead bar made from an extruded hollow profile with longitudinal grooves designed for securing a front edge of the awning canvas and a front skirt, as well as another longitudinal groove for securing the front ends of the awning arms located at a rear section of the profile. The relative arrangement of the longitudinal grooves for securing canvas, skirt and arms allows the profile to be installed in two mutually inverted positions that are respectively suitable for rigid oscillating or elbow-like articulated arms. In each case, the canvas-securing groove is located in the upper section and as close as possible to the lead bar when the arms are completely folded. This profile includes a wide region and an elongated region, but the longitudinal grooves for securing canvas and arms are not located on said wide portion in relative opposite positions with respect to its central axis.

Utility model DE-A-9403139 describes a lead bar for a retractable awning with the features of the preamble of claim 1.

A purpose of the present invention is to reduce the inconveniences of the profiles of the previous art by providing a lead bar for a retractable awning adapted to withstand the combined flexion and torsion efforts in main planes and axes and in other multiple variable planes.

DESCRIPTION OF THE INVENTION

The present invention contributes to reach the previous and other objectives by providing a lead bar for a retractable awning of the type that is made up of a hollow profile obtained by extrusion of a light metal alloy, and comprising a longitudinal canvas-securing groove for fixing the front edge of an awning canvas and a longitudinal arm-securing groove for securing the front end of at least one arm. Said profile has a cross-section with a surrounding wall that defines a wide region, in which said surrounding wall comprises upper, lower, front and rear portions located away from a central geometric axis, and an elongated region, in which said surrounding wall comprises front and rear sections facing each other and located close to a geometric mid-plane between them. The mentioned elongated region overhangs downwards from said lower portion of the wide region next to the front edge of the same. The cited longitudinal canvas-securing groove and said longitudinal arm-securing groove are arranged on said upper portion and lower portion of the wide portion respectively in substantially directly opposite positions in relation to said central axis. The lead arm of the present invention is characterised in that in that said profile comprises a partition wall that separates the wide region from the elongated region, said partition wall connecting an interior part of said longitudinal arm-securing groove and an area of the surrounding wall where said front portion of the wide region and said elongated front section of the elongated region meet together.

This partition wall reinforces the profile and endows additional rigidity in the wide region against any eventual strain caused by combined torsion and flexion efforts.

In exemplary embodiments, the lower portion of the wide region is connected to said rear long section forming a concavity with respect to the outside of the bar at a right, or almost right, angle, and the longitudinal arm-securing groove is formed in said concavity.

In exemplary embodiments, the contour of the wide region is similar to a circle, or preferably, an ellipse having a horizontal axis slightly longer than a vertical axis when said arm is substantially horizontal, thereby providing the profile with excellent resistance to torsion with respect to the central axis of the wide region and increased resistance to flexion in a horizontal plane through this central axis. Similarly, the mentioned mid-plane in the elongated region is substantially vertical when the arms are substantially horizontal, thereby providing the profile with excellent resistance to flexion in a vertical plane.

Thus, the lead bar according to the present invention achieves excellent resistance to torsion along its longitudinal axis and also to flexion in the horizontal and vertical planes, with a minimum of weight and without renouncing to an attractive aesthetic appearance.

A BRIEF DESCRIPTION OF THE DRAWINGS

The previous and other advantages and features will be more fully understood from the following detailed description of exemplary embodiments with reference to the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of a lead bar for a retractable awning according to an exemplary embodiment of the present invention;

FIG. 2 is a side view of the mounting of the lead bar shown in FIG. 1;

FIG. 3 is a diagram showing the torsion moment to which the lead bar is subjected during use and the forces causing it;

FIG. 4 is a diagram that illustrates the flexion moment in the horizontal plane to which the lead bar is subjected during use and the forces causing it;

FIG. 5 is a diagram that illustrates the flexion moment in the vertical plane to which the lead bar is subjected during use and the forces causing it;

FIG. 6 is a cross-sectional view of a lead bar for a retractable awning according to another exemplary embodiment of the present invention; and

FIG. 7 is a side view of the mounting of the lead bar of FIG. 6.

A DETAILED DESCRIPTION OF AN EXEMPLARY EMBODIMENT

First with reference to FIG. 1, a hollow profile 1 is shown in cross-section, said hollow profile 1 being obtained by extrusion of a light metal alloy, such as aluminium, from which the lead bar according to an exemplary embodiment of the present invention is constituted. Profile 1 has a surrounding wall 8 that defines a wide region A wherein upper, lower, front and rear portions 8 a, 8 b, 8 c, 8 d of said surrounding wall 8 are located away from a central axis E. Surrounding wall 8 of profile 1 also defines an elongated region B wherein said surrounding wall 8 includes front and rear elongated sections 8 e, 8 f facing each other and close to a mid-plane P located between them.

Mentioned elongated region B of the cross-section of profile 1 projects downwards from the wide region A, next to a front side of profile 1. The mentioned lower portion 8 b of the surrounding wall 8, which forms part of the wide region A, is connected to said elongated rear section 8 f of elongated region B forming a concavity with respect to the exterior in a right, or almost right, angle. The lower portion 8 b of the wide region A comprises in said concavity a longitudinal arm-securing groove 6 intended to secure the front ends of arms 7 (FIG. 2) by means of known conventional securing elements. The lower portion 8 b is connected to said rear portion 8d of the surrounding wall 8 that forms part of the wide region A, and both are jointly shaped to mate with a support surface 9 of an articulated connection piece 10 installed at the end of arm 7, as shown in FIG. 2. Elongated region B partially hides the connection of arm 7 with profile 1, thus contributing to improve the aesthetic appearance of the assembly.

In the mentioned upper portion 8a of the wide region A, the profile from which the lead bar is constituted includes a longitudinal canvas-securing groove 2 intended to secure the front edge of an awning canvas 3 (FIG. 2) by conventional means well-known to those skilled in the sector art. The mentioned longitudinal canvas-securing groove 2 has a longitudinal opening facing forward and downward to facilitate expulsion of water, for example, rainwater, that might have penetrated into the longitudinal canvas-securing groove 2. The mentioned front portion 8 c of surrounding wall 8 that forms part of the wide region A is connected without a continuity solution to said elongated front section 8 e of elongated region B forming a continuous curved section from the longitudinal canvas-securing groove 2 to a longitudinal skirt-securing groove 4. In this exemplary embodiment, the profile 1 seen in cross-section also includes a partition wall 11 that separates the wide region A from the elongated region B. More specifically, the mentioned partition wall 11 connects an interior part of the longitudinal arm-securing groove 6 to an area of the surrounding wall 8 where the mentioned front portion 8 c of the wide region A and the elongated front section 8 e of elongated region B meet together.

Referring now to FIGS. 3 to 5, the forces intervening in the creation of torsion and flexion efforts in the profile are described. In order to facilitate this explanation, a system of orthogonal coordinated axes have been established in which the X axis is parallel to the longitudinal direction of the profile and therefore parallel to the central axis E, the Y axis is horizontal and the Z axis is vertical.

FIG. 3 is a diagram illustrating on plane Y, Z the forces that intervene in the creation of a torsion effort in the profile. Arms 7 are spring loaded to push profile 1 in a direction that takes the lead bar away from the wall or structure on which the awning is installed, and the thrust of arms 7 is balanced by the tension of canvas 3 retained by the roll-up tube. A tension T corresponding to the tension in canvas 3 is applied to the longitudinal canvas-securing groove 2, and tension T can be decomposed into a vertical tension component Tv and a horizontal tension component Th. A force F corresponding to the thrust of arms 7 is applied to the longitudinal arm-securing groove 6, and force F can be decomposed into a vertical force component Fv and a horizontal force component Fh. The horizontal tension and force components Th and Fh constitute a pair of forces that produce a torsion moment Mt.

The longitudinal arm- and canvas-securing grooves 2, 6 are arranged in the wide region A so that an imaginary line from one to the other would approximately pass through the central axis E or close to it. Also, the distances from the longitudinal arm- and canvas-securing grooves 2, 6 to the central axis E are substantially equal. In other words, longitudinal arm- and canvas-securing grooves 2, 6 are substantially in directly opposite positions in relation to said central axis E. In wide region A, the surrounding wall 8 defines a contour similar to a circle, or an ellipse having two axes of similar, or not very different, lengths. This circular or elliptical contour of the mentioned wide region A is the most suitable for providing good resistance to torsion with respect to the central axis E, and it was selected for this reason. Partition wall 11, mentioned above, reinforces profile 1 and provides additional rigidity against any eventual strain in the wide region A produced by torsion effort with respect to the central axis E.

FIG. 4 is a diagram illustrating on plane X, Y the forces that intervene in the creation of a flexion effort in the horizontal plane on the profile. The tension T of canvas 3 is applied in an approximately uniform fashion along the entire length of profile 1, although for greater simplicity in FIG. 4, the horizontal tension component Th is shown concentrated at a central point of profile 1. On the other hand, the horizontal force components Fh of the two arms 7 are applied at the ends of profile 1. This combination of horizontal tension and force components Th and Fh produce a flexion moment in a horizontal plane Mfh in profile 1. In order to increase the resistance to flexion of the profile in the horizontal plane without losing any capacity to withstand the torsion with respect to the central axis E, the contour of the wide region A is preferable similar to an ellipse having a horizontal axis that is slightly longer than a vertical axis. The partition wall 11 also contributes to the reinforcement of profile 1 against flexion forces in the horizontal plane.

FIG. 5 illustrates on plane X, Z the forces that intervene in the creation of a flexion force in a vertical plane in the profile. Profile 1 has its own weight Pp that is applied in an approximately uniform fashion along the entire length of profile 1, although for greater simplicity in FIG. 5, own weight Pp, which obviously acts in a vertical direction, is shown concentrated at a central point of profile 1. Own weight Pp also includes part of the weight of canvas 3. This own weight is balanced by a supporting resistance produced by the two arms 7. Thus, vertical supporting resistance components Rv are applied to the ends of profile 1. This combination of own weight Pp and vertical supporting resistance components Rv produce a flexion moment in a vertical plane Mfv in profile 1. In order to increase the flexion resistance of profile 1 in the vertical plane without negatively affecting the torsion resistance with respect to the central axis E and the flexion resistance in the horizontal plane, profile 1 includes the elongated region B described above, which is arranged so that the mentioned mid-plane P is substantially vertical. Moreover, at the end of the elongated region B furthest away from wide region A, where the ends of the elongated front and rear sections 8 e, 8 f meet together, profile 1 includes a longitudinal skirt-securing groove 4 intended to secure a skirt 5 (FIG. 2) by conventional means similar to said means for securing canvas 3. The mentioned longitudinal skirt-securing groove 4 has a longitudinal opening facing downwards. With this arrangement, the longitudinal skirt-securing groove 4 and the longitudinal canvas-securing groove 2 add mass to profile 1 at locations that are spaced apart as much as possible from each other in the vertical direction and relatively close to mid-plane P in order to contribute to improve the moment of inertia of the profile against flexion in the vertical plane.

FIGS. 6 and 7 show another exemplary embodiment of the lead bar of the present invention, which is very similar to the exemplary embodiment described above in relation to FIGS. 1 and 2, for which reason it will not be described in detail. The main difference lies in the fact that elongated region B is longer, which makes it more appropriate for very wide awnings with a significantly longer lead bar, since it has a greater resistance to flexion in the vertical plane. In all the exemplary embodiments, as usual, the lead bar is completed with plastic end pieces (not shown) that are fitted to the ends of the profile 1 to close off the internal cavities of the hollow profile 1 in order to prevent the accumulation of dust and other dirt and also to improve its appearance.

Those skilled in the art would be able to introduce variations and modifications in the described and illustrated exemplary embodiments without departing from the scope of the present invention as defined in the attached claims. 

1.-11. (canceled)
 12. A lead bar for a retractable awning, of the type constituted from a hollow profile obtained by extrusion of a light metal alloy, comprising: a longitudinal canvas-securing groove for fixing the front edge of an awning canvas and a longitudinal arm-securing groove for securing the front end of at least one arm, said profile having a cross-section with a surrounding wall that defines: a wide region, in which said surrounding wall comprises upper, lower, front and rear portions located away from a central geometric axis; and an elongated region, in which said surrounding wall comprises elongated front and rear sections facing each other and located close to a geometric mid-plane between them, said elongated region projecting downwards from said lower potion of the wide region next to a front edge thereof; said longitudinal canvas-securing groove and said longitudinal arm-securing groove are arranged respectively on said upper portion and on the lower portion of the wide region in substantially directly opposite positions in relation to said central axis, said profile comprising a partition wall that separates the wide region from the elongated region, said partition wall connecting an interior part of said longitudinal arm-securing groove and an area of the surrounding wall where said front portion of the wide region and said elongated front section of the elongated region meet together.
 13. A lead bar, in accordance with claim 12, wherein the lower portion of the wide region and said elongated rear section of the elongated region are connected together at a right, or almost right, angle forming a concavity, the longitudinal arm-securing groove being formed in said concavity.
 14. A lead bar, in accordance with claim 13, wherein at least parts of the lower portion and of said rear portion of the wide region are shaped to fit with a support surface of an articulated connection piece that is mounted on the end of the arm.
 15. A lead bar, in accordance with claim 12, wherein the longitudinal canvas-securing groove has a longitudinal opening facing forward and downward for facilitating evacuation of water therefrom.
 16. A lead bar, in accordance with claim 12, further comprising a longitudinal securing skirt groove, for securing a skirt, said longitudinal securing skirt groove being formed at one end of the elongated region that is furthest away from the wide region, where the lower ends of the elongated front and rear sections meet together.
 17. A lead bar in accordance with claim 12, wherein said front portion of the wide region is connected without a continuity solution to said elongated front section of elongated region.
 18. A lead bar in accordance with claim 12, wherein the contour of the wide region is similar to a circle or an ellipse.
 19. A lead bar in accordance with claim 12, wherein the contour of the wide region is similar to an ellipse having an horizontal axis slightly longer than a vertical axis, when said arm is in a substantially horizontal position.
 20. A lead bar in accordance with claim 12, wherein said mid-plane is substantially vertical or close to vertical when said arm is in a substantially horizontal position. 